The application relates to an improvement in contact pins for providing an electrical contact between a battery and a circuit board in a remote signaling device.
Modern vehicles are provided with a remote signaling device typically known as a key fob. A key fob includes an RF receiver/transmitter and a plurality of switches. The switches are utilized to communicate a signal to a vehicle remotely, and instruct changes in status for various components on the vehicle. Typically, the key fob will include the ability to request the doors to be opened or locked, and the trunk to be opened. Other commands such as memory function, remote ignition, etc. are often also incorporated into these remote signaling devices.
The remote signaling devices are also provided with a small replaceable battery. Typically, the battery is generally cylindrical and received between structural mounts which provide electrical contacts on each of the two exposed faces of the battery. The structural mounts have typically been generally cylindrical sections which extend for a good deal of distance circumferentially. These mounts have been relatively complex to manufacture and assemble. Due to the unique shape of these generally cylindrical sections, the insertion of these contacts into the circuit board has typically required manual assembly.
The key fobs are manufactured in the millions, and the requirement for manual assembly steps is undesirable. It would be desirable to provide contacts which could be assembled by automatic processes. Further, it would be desirable to provide a less expensive contact structure.
In the disclosed embodiment of this invention, the contact pin is force fit into the opening in the circuit board. The contact pin has an upper enlarged portion and a generally elongate thinner extending portion. The extending portion extends along the length of the battery and the enlarged portion fits over the top of the battery. Preferably, the pin is generally symmetrical. Since the pin is symmetrical, its orientation relative to the circuit board is unimportant, which facilitates automatic insertion of the pin into the board. Most preferably, the pin is generally cylindrical and the enlarged portion is generally spherical. A transition portion between the elongate portion and the spherical portion is preferably generally tapered, or frustro-conical.
Further, at the remote end of the pin from the enlarged portion is an enlarged tab which abuts the upper surface of the board, and provides a stop for the pin into the hole in the board. In this fashion, the pin is not inserted into the board for too great a distance, such that it is at the proper desired height relative to the battery.
Stated another way, the pin is preferably of a dimension such that it extends circumferentially for about the same distance as it extends radially. The term xe2x80x9caboutxe2x80x9d as utilized in context of this application would require that the radial dimension is at least 66% of the circumferential dimension, more preferably within 80%, and most preferably the pin is symmetric such that the two dimensions are effectively equal.
These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description.